Explicitly register each key system.

content/renderer/media/crypto/key_systems_info.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/crypto/key_systems_info.h"
 
 #include "base/logging.h"
+#include "content/renderer/media/crypto/key_systems.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 
 #include "widevine_cdm_version.h" // In SHARED_INTERMEDIATE_DIR.
 
 // The following must be after widevine_cdm_version.h.
 
 #if defined(WIDEVINE_CDM_AVAILABLE) && \
     defined(OS_LINUX) && !defined(OS_CHROMEOS)
 #include <gnu/libc-version.h>
 #include "base/logging.h"
 #include "base/version.h"
 #endif
 
 #if defined(DISABLE_WIDEVINE_CDM_CANPLAYTYPE)
 #include "base/command_line.h"
 #include "media/base/media_switches.h"
 #endif
 
 namespace content {
 
 static const char kClearKeyKeySystem[] = "webkit-org.w3.clearkey";
 
 #if defined(ENABLE_PEPPER_CDMS)
 static const char kExternalClearKeyKeySystem[] =
     "org.chromium.externalclearkey";
 #endif  // defined(ENABLE_PEPPER_CDMS)
 
 #if defined(WIDEVINE_CDM_AVAILABLE)
-// TODO(ddorwin): Automatically support parent systems: http://crbug.com/164303.
-static const char kWidevineBaseKeySystem[] = "com.widevine";
 
 #if defined(WIDEVINE_CDM_CENC_SUPPORT_AVAILABLE)
 // The supported codecs depend on what the CDM provides.
 static const char kWidevineVideoMp4Codecs[] =
 #if defined(WIDEVINE_CDM_AVC1_SUPPORT_AVAILABLE) && \
     defined(WIDEVINE_CDM_AAC_SUPPORT_AVAILABLE)
     "avc1,mp4a";
 #elif defined(WIDEVINE_CDM_AVC1_SUPPORT_AVAILABLE)
     "avc1";
 #else
     "";  // No codec strings are supported.
 #endif
 
 static const char kWidevineAudioMp4Codecs[] =
 #if defined(WIDEVINE_CDM_AAC_SUPPORT_AVAILABLE)
     "mp4a";
 #else
     "";  // No codec strings are supported.
 #endif
 #endif  // defined(WIDEVINE_CDM_CENC_SUPPORT_AVAILABLE)
 
-static inline bool IsWidevine(const std::string& key_system) {
-  return key_system == kWidevineKeySystem ||
-         key_system == kWidevineBaseKeySystem;
+static void RegisterWidevine() {

[xhwang, 2013/08/29 21:45:26]

I <3 this function!

[ddorwin, 2013/08/29 22:20:18]

Done.

+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+  Version glibc_version(gnu_get_libc_version());
+  DCHECK(glibc_version.IsValid());
+  if (glibc_version.IsOlderThan(WIDEVINE_CDM_MIN_GLIBC_VERSION))
+    return;
+#endif  // defined(OS_LINUX) && !defined(OS_CHROMEOS)
+
+  AddConcreteSupportedKeySystem(
+      kWidevineKeySystem,
+      false,
+#if defined(ENABLE_PEPPER_CDMS)
+      kWidevineCdmPluginMimeType,
+#elif defined(OS_ANDROID)
+      { 0xED, 0xEF, 0x8B, 0xA9, 0x79, 0xD6, 0x4A, 0xCE,
+        0xA3, 0xC8, 0x27, 0xDC, 0xD5, 0x1D, 0x21, 0xED },
+#endif  // defined(ENABLE_PEPPER_CDMS)
+      "com.widevine");
+  AddSupportedType(kWidevineKeySystem, "video/webm", "vorbis,vp8,vp8.0");
+  AddSupportedType(kWidevineKeySystem, "audio/webm", "vorbis");
+#if defined(USE_PROPRIETARY_CODECS) && \
+  defined(WIDEVINE_CDM_CENC_SUPPORT_AVAILABLE)

[scherkus (not reviewing), 2013/08/29 20:11:47]

indent by 2 more

[ddorwin, 2013/08/29 21:44:04]

Done.

+  AddSupportedType(kWidevineKeySystem, "video/mp4", kWidevineVideoMp4Codecs);
+  AddSupportedType(kWidevineKeySystem, "audio/mp4", kWidevineAudioMp4Codecs);
+#endif  // defined(USE_PROPRIETARY_CODECS) &&
+        // defined(WIDEVINE_CDM_CENC_SUPPORT_AVAILABLE)
 }
-#endif  // defined(WIDEVINE_CDM_AVAILABLE)
+#endif  // WIDEVINE_CDM_AVAILABLE
 
-const MediaFormatAndKeySystem kSupportedFormatKeySystemCombinations[] = {
+
+void RegisterKeySystems() {
   // Clear Key.
-  { "video/webm", "vorbis,vp8,vp8.0", kClearKeyKeySystem },
-  { "audio/webm", "vorbis", kClearKeyKeySystem },
+  AddConcreteSupportedKeySystem(
+      kClearKeyKeySystem,
+      true,
+#if defined(ENABLE_PEPPER_CDMS)
+      "",
+#elif defined(OS_ANDROID)
+      { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
+        0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, },
+#endif  // defined(ENABLE_PEPPER_CDMS)
+      std::string());

[scherkus (not reviewing), 2013/08/29 20:11:47]

any reason why you use std::string() here but "" on line 94?

I don't care which one ... but consistency is nice

I wonder if this is an appropriate case for string_util's EmptyString()
(although historically we've never bothered to use it in media code)

[ddorwin, 2013/08/29 21:44:04]

Because I added this one later. :)
Done.
I thought std::string() is preferred - is that correct?
I don't think so:
// There is only one case where you should use these: functions which need to
// return a string by reference (e.g. as a class member accessor), and don't
// have an empty string to use (e.g. in an error case).  These should not be
// used as initializers, function arguments, or return values for functions
// which return by value or outparam.

+  AddSupportedType(kClearKeyKeySystem, "video/webm", "vorbis,vp8,vp8.0");
+  AddSupportedType(kClearKeyKeySystem, "audio/webm", "vorbis");
 #if defined(USE_PROPRIETARY_CODECS)
-  { "video/mp4", "avc1,mp4a", kClearKeyKeySystem },
-  { "audio/mp4", "mp4a", kClearKeyKeySystem },
+  AddSupportedType(kClearKeyKeySystem, "video/mp4", "avc1,mp4a");
+  AddSupportedType(kClearKeyKeySystem, "audio/mp4", "mp4a");
 #endif  // defined(USE_PROPRIETARY_CODECS)
 
 #if defined(ENABLE_PEPPER_CDMS)
   // External Clear Key (used for testing).
-  { "video/webm", "vorbis,vp8,vp8.0", kExternalClearKeyKeySystem },
-  { "audio/webm", "vorbis", kExternalClearKeyKeySystem },
+  AddConcreteSupportedKeySystem(kExternalClearKeyKeySystem, false,
+                                "application/x-ppapi-clearkey-cdm",
+                                std::string());
+  AddSupportedType(kExternalClearKeyKeySystem,
+                   "video/webm", "vorbis,vp8,vp8.0");
+  AddSupportedType(kExternalClearKeyKeySystem, "audio/webm", "vorbis");
 #if defined(USE_PROPRIETARY_CODECS)
-  { "video/mp4", "avc1,mp4a", kExternalClearKeyKeySystem },
-  { "audio/mp4", "mp4a", kExternalClearKeyKeySystem },
+  AddSupportedType(kExternalClearKeyKeySystem, "video/mp4", "avc1,mp4a");
+  AddSupportedType(kExternalClearKeyKeySystem, "audio/mp4", "mp4a");
 #endif  // defined(USE_PROPRIETARY_CODECS)
 #endif  // defined(ENABLE_PEPPER_CDMS)
 
 #if defined(WIDEVINE_CDM_AVAILABLE)

[xhwang, 2013/08/29 21:45:26]

Does it make sense to wrap the above to RegisterClearKey(), and
RegisterExternalClearKey()?

[ddorwin, 2013/08/29 22:20:18]

Done. I had considered it and decided not to because it required an extra
#ifdef, but I did it now.

-  // Widevine.
-  { "video/webm", "vorbis,vp8,vp8.0", kWidevineKeySystem },
-  { "audio/webm", "vorbis", kWidevineKeySystem },
-#if defined(USE_PROPRIETARY_CODECS)
-#if defined(WIDEVINE_CDM_CENC_SUPPORT_AVAILABLE)
-  { "video/mp4", kWidevineVideoMp4Codecs, kWidevineKeySystem },
-  { "audio/mp4", kWidevineAudioMp4Codecs, kWidevineKeySystem },
-#endif  // defined(WIDEVINE_CDM_CENC_SUPPORT_AVAILABLE)
-#endif  // defined(USE_PROPRIETARY_CODECS)
+  RegisterWidevine();
 #endif  // WIDEVINE_CDM_AVAILABLE
-};
-
-const int kNumSupportedFormatKeySystemCombinations =
-    arraysize(kSupportedFormatKeySystemCombinations);
-
-#if defined(ENABLE_PEPPER_CDMS)
-const KeySystemPepperTypePair kKeySystemToPepperTypeMapping[] = {
-  { kExternalClearKeyKeySystem, "application/x-ppapi-clearkey-cdm"},
-#if defined(WIDEVINE_CDM_AVAILABLE)
-  { kWidevineKeySystem, kWidevineCdmPluginMimeType}
-#endif  // WIDEVINE_CDM_AVAILABLE
-};
-
-const int kNumKeySystemToPepperTypeMapping =
-    arraysize(kKeySystemToPepperTypeMapping);
-#endif  // defined(ENABLE_PEPPER_CDMS)
-
-#if defined(OS_ANDROID)
-// TODO(qinmin): add UUIDs for other key systems.
-const KeySystemUUIDPair kKeySystemToUUIDMapping[] = {
-#if defined(WIDEVINE_CDM_AVAILABLE)
-  { kWidevineKeySystem, { 0xED, 0xEF, 0x8B, 0xA9, 0x79, 0xD6, 0x4A, 0xCE,
-                          0xA3, 0xC8, 0x27, 0xDC, 0xD5, 0x1D, 0x21, 0xED }
-  }
-#endif  // defined(WIDEVINE_CDM_AVAILABLE)
-};
-
-// arraySize() does not work if the array is empty, so use ARRAYSIZE_UNSAFE().
-const int kNumKeySystemToUUIDMapping =
-    ARRAYSIZE_UNSAFE(kKeySystemToUUIDMapping);
-#endif  // defined(OS_ANDROID)
-
-bool IsOSIncompatible(const std::string& concrete_key_system) {
-  DCHECK(IsConcreteKeySystem(concrete_key_system))
-      << concrete_key_system << " is not a concrete system";
-#if defined(WIDEVINE_CDM_AVAILABLE) && \
-    defined(OS_LINUX) && !defined(OS_CHROMEOS)
-  if (IsWidevine(concrete_key_system)) {
-    Version glibc_version(gnu_get_libc_version());
-    DCHECK(glibc_version.IsValid());
-    return glibc_version.IsOlderThan(WIDEVINE_CDM_MIN_GLIBC_VERSION);
-  }
-#endif
-  return false;
-}
-
-std::string EnsureConcreteKeySystem(const std::string& key_system) {
-#if defined(WIDEVINE_CDM_AVAILABLE)
-  if (key_system == kWidevineKeySystem || key_system == kWidevineBaseKeySystem)
-    return kWidevineKeySystem;
-#endif  // WIDEVINE_CDM_AVAILABLE
-  // No parent names for Clear Key.
-  if (key_system == kClearKeyKeySystem)
-    return kClearKeyKeySystem;
-#if defined(ENABLE_PEPPER_CDMS)
-  // No parent names for External Clear Key.
-  if (key_system == kExternalClearKeyKeySystem)
-    return kExternalClearKeyKeySystem;
-#endif  // defined(ENABLE_PEPPER_CDMS)
-  return std::string();
 }
 
 bool IsCanPlayTypeSuppressed(const std::string& key_system) {
 #if defined(DISABLE_WIDEVINE_CDM_CANPLAYTYPE)
   // See http://crbug.com/237627.
-  if (IsWidevine(key_system) &&
+  if (key_system == kWidevineKeySystem &&
       !CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kOverrideEncryptedMediaCanPlayType))
     return true;
 #endif
   return false;
 }
 
 std::string KeySystemNameForUMAInternal(const WebKit::WebString& key_system) {
   if (key_system == kClearKeyKeySystem)
     return "ClearKey";
 #if defined(WIDEVINE_CDM_AVAILABLE)
   if (key_system == kWidevineKeySystem)
     return "Widevine";
 #endif  // WIDEVINE_CDM_AVAILABLE
   return "Unknown";
 }
 
-bool CanUseAesDecryptorInternal(const std::string& key_system) {
-  return  key_system == kClearKeyKeySystem;
-}
-
 } // namespace content